function rate_expect_out=Expected_Rate(idle_prob,SNR_var,frame_duration,sensing_duration,iteration,rate_expect_in)
vadility_ratio=1-iteration.*sensing_duration./frame_duration;
F = @(t)exp(-t)./t;
rate_expect_idle = quad(F,exp((rate_expect_in)./vadility_ratio)./SNR_var,500); 
rate_expect_out=idle_prob.*exp(1/SNR_var).*vadility_ratio.*rate_expect_idle+rate_expect_in;
end